These great hollow globes of artificial super-metals, and artificial transparent adamant, ranged in size from the earliest and smallest structures, which were no bigger than a very small asteroid, to spheres considerably larger than the Earth. (Olaf Stapledon, STAR MAKER)

Sunday, November 9, 2014

Structure

Today's Pluto Picture of the Day shows interior models for the various moons and dwarf planets of our Solar System. Interesting how many of these have been shown (or are theorized) to contain liquid water (as well as water ice). How big will the "habitable zone" become?